Be careful when using DATE objects against a DATETIME field. Saying WHERE [SomeDate] BETWEEN '7/24/16' AND '7/30/16' for example will give you everything in the range of:
2016-07-24 00:00:00.000
to
2016-07-30 00:00:00.000
Which means entries on 7/30/16 after midnight would be omitted. To get around this you have two options:
1. Cast the DATETIME field to a DATE (this sometimes has performance issues)
2. Alter the above so the resulting calculation ends up as 2016-07-30 23:59:59.999 which would be like this:

Now, there are a couple of quirks here. SQL Server's DATETIME object doesn't exactly have the precision required to render to the single millisecond even though it does have the scale to do so. Adding -1 millisecond actually will do nothing to the final output. Adding -2 milliseconds will leave you with 2016-07-30 23:59:59.997. So what you have is a 3 millisecond gap that you can't really pin down. Of course the chances of one of your entries being exactly inside that 3 millisecond gap around midnight are extremely slim.

If you need the performance then you can pre-calculate these date values and use them in your query. You gain performance at the expense of those 3 milliseconds. If you absolutely must have the millisecond accuracy then you'll need to cast the column as a DATE. Or if you don't care at all or your column is already a DATE then you're good to go.

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